When a Swedish man drove down a deserted forest road near Umeaa, Sweden last December 19th, he was probably looking forward to Christmas. But that day, his car somehow became buried under a mountain of snow. He was trapped there for two months, suffering insanely low temperatures, with no access to food. Last Sunday, he was discovered. Alive. But how?

The Swedish police believe his story. But he was hardly Captain America, so how the hell did he survive in temperatures as low as that, for two months, without food?

Coping without food

The body can survive without food for a respectable length of time. The upper limit does, however, seem to be about two months under normal conditions—and even then, the results aren't pretty. As an example, Barry Horne, a British animal rights protester, went on hunger strike whilst in prison. His experiences are well documented:

"On day 43 of his hunger strike he received the last rights and was placed in a "hunger strike cell", fitted with just a cardboard chair and table. By day 66 he was hallucinating, deaf in one ear and blind in one eye; he could no longer remember why he was on hunger strike. After 68 days without food he ended his ordeal."

But the Swedish dude isn't reported to have any of those problems: he's emaciated and malnourished, sure, but hasn't undergone that level of physical stress.

Slowing down in the cold

The key is the accompanying drop in temperature. When the body gets cold, its core temperature—right inside your torso, the temperature at which your vital organs operate—drops in order to slow your metabolism. If you get hypothermic, your heart rates slow, and your body uses less energy and oxygen.

There are some extreme examples of the phenomenon. A 7-year-old in Sweden who was found in freezing sea water made a full recovery, despite the fact that her core temperature had dropped to 13C and she was, for all intents and purposes, dead. That, however, was a much shorter time scale: hours, as opposed to months.

Fortunately, our Swedish guy in the car had warm clothes; he had a sleeping bag; he had shelter. Tucked up in the back of the car, his core temperature dropped to 31C. Fortunately for him, he hit a sweet spot. His body's metabolic rate dropped dramatically, meaning he used extremely little energy, but his body didn't shut down entirely. As one of his physicians has explained:

"A bit like a bear that hibernates. Humans can do that. He probably had a body temperature... which the body adjusted to. Due to the low temperature, not much energy was used up."

Crucially, he didn't get too cold: if temperatures were much lower, his breathing and heart rate would have slowed to the point that, over hours or days, his brain would have been starved of oxygen. On the flip side, he wasn't too hot: much warmer, and his body wouldn't have had the energy reveres to see him through the two months. He took on a death-defying balancing act, and won. On balance, he was one lucky son of a bitch. [MSNBC Image: nathanmac87]